***

title: CLI SSH Authentication (macOS)
description: >-
Resolve Brev CLI SSH authentication failures caused by invalid or corrupted
SSH keys on macOS.
------------------

This guide helps you resolve Brev CLI authentication failures on macOS when SSH key issues prevent connection to your instances.

<Callout intent="note">
  **Platform**: macOS
</Callout>

## Problem

On macOS systems, Brev CLI commands such as `brev ls`, `brev login`, or `brev ssh` fail with authentication or connection errors.

**Typical symptoms include:**

* `Permission denied (publickey)`
* `Could not establish SSH connection`
* `Error: connection closed unexpectedly`

This issue occurs when the local SSH key used by Brev (`~/.brev/brev.pem`) becomes invalid, corrupted, or has incorrect file permissions.

## Prerequisites

* macOS with Brev CLI installed (`brew install brevdev/homebrew-brev/brev`)
* Access to Brev dashboard or web app
* Terminal access with user home directory permissions

## Solution

Choose one of the following approaches to resolve the issue.

### Option 1: Re-authenticate Using Token (Recommended)

<Steps>
  ### Open account settings

  Go to Brev Dashboard → Account Settings: [https://brev.nvidia.com/settings/account](https://brev.nvidia.com/settings/account)

  ### Navigate to CLI settings

  Click on **CLI** in the settings menu.

  ### Copy the token

  Copy the authentication token displayed on the page.

  ### Authenticate in terminal

  Paste the token in your terminal when prompted by:

  ```bash
  brev login --token
  ```

  ### Verify connection

  ```bash
  brev ls
  ```

  The command should list all available instances without error.
</Steps>

### Option 2: Regenerate SSH Key

<Steps>
  ### Check for existing Brev key

  ```bash
  ls -l ~/.brev/brev.pem
  ```

  If the file is missing or has incorrect permissions, proceed to the next step.

  ### Backup and remove old key

  ```bash
  mv ~/.brev/brev.pem ~/.brev/brev.pem.bak
  ```

  ### Generate a new Brev key

  1. Go to the [Brev Dashboard](https://brev.nvidia.com)
  2. Navigate to **Profile → SSH Keys**
  3. Re-download or generate a new `.brev.pem` file

  ### Set correct file permissions

  ```bash
  chmod 600 ~/.brev/brev.pem
  ```

  ### Re-authenticate with Brev

  ```bash
  brev login
  brev ls
  ```

  Verify the connection is successful.
</Steps>

## Verification

After completing either option:

* `brev ls` lists all available instances without error
* `brev ssh <instance-name>` connects successfully to the instance
* No permission or key errors appear in terminal output

## Workaround

If key regeneration fails:

* Temporarily use the [Brev Web Dashboard](https://brev.nvidia.com) for instance access
* Restore the previous key if needed:

```bash
mv ~/.brev/brev.pem.bak ~/.brev/brev.pem
chmod 600 ~/.brev/brev.pem
```